Apparatus for wireless telegraphy.



UNITED STATES r rnur OFFICE.

GUGLIELMO MARCONI. OE ADELPHI, LONDON, ENGLAND, ASSIGNOR' TO MARCONIWIRE- LESS TELEGRAPH' COMPANY OF AMERICA, OF NEW YORK, N. Y., ACORPORATION OF NEW JERSEY. I

To all whom it may concern:

Be it known that I, GUcLinLMo MARCONI, LL. 1)., D. So, a subject of theKing of Italy, residing at W'a'tergate House Adelphi, London, England,have invented new and useful Improvements in Apparatus for WirelessTelegraphy, of which the follow ing is a specification.

According to this invention instead of the usual spark or arc in the.oscillating circuit of a wireless telegraph transmitter, the dischargeis caused to take place across a small gap between metal surfaces inrelative motlon at a very high speed. One of the surfaces mayconveniently be a disk or similar rotatable device having a continuoussurface and adapted to rotate so that its peripheral speed isone hundredmeters per second or more while the other surface may likewise be arapidly rotating disk or similar device in which case the actual speedof each disk need not be so great though the relativespeed shouldpreferably reach the value given. The disk may be entirely insulated androtate between a pair of disks which are connected in an oscillatorycircuit containing a condenser and an inductance, the condenser beingconnected to a source of electromotive force. Or there may be a pair ofdisks rotating in the same plane, in the same direction and in close.proximity to one another, the two disks being included in' theoscillatory circuit.

The drawings are diagrammatic representations of transmitters made inaccord auce with this invention. 4

In Figure 1 (1 is a metal disk which is'car-' ried on a stand I)insulated from the ground and is capable of being rotated at a very highspeed from anelectric motor turbine or other convenient machineconnected for instance to the belt pulley a. 0 c are disks supported oneon each side of and very close to the disk rt by insulated uprights d(Z. These disks are connected to a condenser e and ind uctance f, thiscircuit being connected either inductively as shown or else conductivelyto an aerial conductor or antenna g which is connected to earth or to acapacity in the usual way. Each plate of the condenser c is connected toa generator h, suitable inductances or resistances i being included inthe connections. The disks 0 may be rotated if desired and may be cooledby water circulation or otherwise.

APPARATUS FOR WIRELESS TELE'GRAPHY.

Specification of Letters Patent. Patented Sept. 28, 1909- Applicationfiled April 10,

190s. SeriaLNo. 426,184.

I11.Fig. 2 the balls or disks are replaced by a disk 0 which can bedriven by means of the pulley c and inay besimilar to a which is nowconnected in the circuit of the condenser and inductance as shown.

In all cases the source of electromotive force h may be a continuouscurrent dynamo, alternator, battery, or transformer.

By the arrangements of my invention as above set forth I am enabled toproduce e1ectrical oscillationsin the sending or transmitting circuitwithout using a. makeandbreak interrupter or other similar device forpro ducing intermittent currents or discharges through the spark gap.The spark gaps are short and therefore require comparatively littlepower to produce the disruptive discharges and the oscillations. Thehigh relative periphe'al speed of the disks forming the spark gap orgaps prevents arcs from 7 forming and produce rapid oscillations. Suchspeed must be above a certain critical point, depending upon the size ofsaid disks, and Whenthe speed is above this critical -point, oscillatorydisrupting discharges are produced between the disks, without thetormation of arcs and without the use of other circuit interruptingdevices. No complete explanation of the phenomenon involved in theproduction'of such discharges is at pres- 35 ent apparent, but I havefound that the apparatus is extremely efiicient for producing theresultsattained, as Well as being of an usually simple construction. There areno metallic contact breaking points to become worn orwhich may get outof adjustment.

If it be necessary to use a higher-electromotive force than that whichis suiiicient to arise a discharge across one or two small gaps thenumber of sparks may be'increased.

The oscillations transmitted through space can be detected at areceiving station by means of the well known receivers or detectorsemployed for wireless telegraphy, it being especially desirable whenusing trans- 1 mitters constructed in accordance with this invention toutilize to the utmost the principle of resonance in'the receivers whichshould preferably contain a responsive oscillation circuit with aslittle damping as possible. What I claim is 1. A transmitter forWireless telegraph apparatus comprising,a plurality of metall c bodieshaving continuous surfaces and lo cated adjacent each other so as toform a 110 means for -ausing a movement of said bodies velocity.

spark gap. means for causing a movement of said bodies so'that saidsurfaces have a high relative velocity to produce disruptive dis-- rl1arges in the gap between said bodies.

2. transmitter for wireless telegraph apparatus comprising. a pluralityof metallic bodies having continuous peripheral surfaces and locatedadjacent each other so as to form relatively short spark gaps. means forcausing a movement of said bodies sothat. the surfaces of a pluralitythereof have a high relative velocity to the surface of another of saidbodies, thereby producing disruptive dis charges in the gaps betweensaid bodies.

2-). In a transmitting apparatus for wireless telegraphv, an oscillationgenerator comprising rotatable bodies having continuous surlacesseparated b v a relatively small spark gap. a condenser having itsterminals connected with 1 said bodies respectively. means for chargingsaid condenser. and

so that their surfaces have a high relative t. In a transmittingapparatus for wire less telegraphy. an oscillation generator comprisinga disk having a continuous rim, a disk situated to form a spark gap withthe first named disk, means for causing a rela tive movement of saiddisks, so that their surfaces have a high relative velocity, conductorsleading from the source of current to said disks respectively, acondenser connected in shunt between said conductorsQand l an aerialoperatively connected with said col'iductors.

In transmitting apparatus for wireless telegraphy, an oscillationgenerator comprising terminals consisting of two adjacent and rotatabledisks, an intermediate disk situated so as to form spark gaps with saidterminal disks. means for causing a relative movement of said disks sothat their surfaces have a high relative velocity. conductors leading-from the source of current to the t'erminal-v disks, a condenserconnected in shunt between said conductors. and a transformer in one ofsaid c'oiuluctors. connecting the same with the aerial.

(3. In a transmitting apparatus fonwireless telegraplrv. an oscillationgenerator comprising disks of metal, a source of direct current. meansfor producing uniform polarity of high potential at the periphery ofsaid disks, :1 eoiuluctor leading from one pole of the source of currentto one disk and operatively connected with an aerial, a second conductorleading from the other pole to the other disk. a condenser placed inshunt be tween the two conductors, an intermediate disk between thefirst named disks. and means for. rotating said intermediate disk at ahigh speed.

GUGLTELMO MARC/0N1.

\Vit nesses .lliuvnv W. ALLEN. (l. WAiau-us.

